Page 264 of 640

2644-5. Using the driving support systems
RC300h_EE(OM24740E)
■Automatic cancelation of vehicle-to-vehicle distance control mode
Vehicle-to-vehicle distance co ntrol driving is automatically canceled in the following situ- ations:
●Actual vehicle speed falls below approximately 40 km/h (25 mph).
●VSC is activated.
●TRC is activated for a period of time.
●When the VSC or TRC system is turned off by pressing the VSC OFF switch.
●The sensor cannot detect correctly because it is covered in some way.
●The windshield wipers are operating at high speed (when the wipers are in AUTO
mode or the high speed wiper operation).
●When snow mode is set.
●Pre-crash braking is activated.
If vehicle-to-vehicle distance control mode is automatically canceled for any other rea- son, there may be a malfunction in the syst em. Contact any authorized Lexus dealer or repairer, or another duly qua lified and equipped professional.
■Automatic cancelation of constant speed control mode
Constant speed control mode is automatically canceled in the following situations:
●Actual vehicle speed is more than approximately 16 km/h (10 mph) below the set vehi-
cle speed.
●Actual vehicle speed falls below approximately 40 km/h (25 mph).
●VSC is activated.
●TRC is activated for a period of time.
●When the VSC or TRC system is turned off by pressing the VSC OFF switch.
●Pre-crash braking is activated.
Page 265 of 640
2654-5. Using the driving support systems
4
Driving
RC300h_EE(OM24740E)
■Radar sensor and grille cover
Always keep the sensor and grille cover clean to ensure that the vehicle-to-vehicle dis- tance control mode operates properly. (Some ob structions, such as snow, ice and plastic
objects, cannot be detected by the obstruction sensor.) Dynamic radar cruise control is canceled if an obstruction is detected.
■Operation guide display
When the dynamic radar cruise control switch is operated, a guidance display is shown
on the meters for a few seconds as to how to operate the dynamic radar cruise control switch or distance switch. ( P. 126)
■Warning messages and buzzers for dynamic radar cruise control
Warning messages and buzzers are used to indicate a system malfunction or to inform the driver of the need for caution while driving. ( P. 548)
Grille cover
Radar sensor
1
2
Page 269 of 640
2694-5. Using the driving support systems
4
Driving
RC300h_EE(OM24740E)
WARNING
■Situations unsuitable for dynamic radar cruise control
Do not use dynamic radar cruise control in any of the following situations. Doing so may result in inappropriate speed control and could cause an accident result-
ing in death or serious injury.
●Roads where there are pedestrians, cyclers, etc.
●In heavy traffic
●On roads with sharp bends
●On winding roads
●On slippery roads, such as those covered with rain, ice or snow
●On steep downhills, or where there are sudden changes between sharp up and down gradients Vehicle speed may exceed the set sp eed when driving down a steep hill.
●At entrances to freeways and highways
●When weather conditions are bad enough that they may prevent the sensors from detecting correctly (fog, snow, sandstorm, heavy rain, etc.)
●When an approach warning buzzer is heard often
●During emergency towing
Page 270 of 640
2704-5. Using the driving support systems
RC300h_EE(OM24740E)
WARNING
■When the sensor may not be correctly detecting the vehicle ahead
In the case of the following and depending on the conditions, operate the brake pedal when deceleration of the system is insufficient or operate the accelerator pedal when
acceleration is required. As the sensor may not be able to correctly detect these types of vehicles, the approachwarning ( P. 262) will not be activated, which may lead to an accident resulting in
death or serious injury.
●Vehicles with small rear ends (trailers with no load on board, etc.)
●Vehicles that cut in suddenly
●Vehicles traveling at low speeds
●Vehicles that are not moving in the same lane
●Motorcycles traveling in the same lane
Page 271 of 640
2714-5. Using the driving support systems
4
Driving
RC300h_EE(OM24740E)
WARNING
■Conditions under which the vehicle-to-vehicle distance control mode may not func- tion correctly
Operate the brake pedal (or accelerator pedal operation depending on the situation)
as necessary in the following conditions as the radar sensor may not be able to cor- rectly detect vehicles ahead, which may lead to an accident resulting in death or seri-ous injury.
●When water or snow thrown up by the surrounding vehicles hinders the detecting ofthe sensor
●When your vehicle is pointing upwards(caused by a heavy load in the trunk, etc.)
●When the road curves or when the lanes arenarrow
●When steering wheel operation or your posi-tion in the lane is unstable
●When the vehicle ahead of you decelerates
suddenly
Accelerate Accelerate Decelerate
Page 272 of 640

2724-5. Using the driving support systems
RC300h_EE(OM24740E)
WARNING
■Handling the radar sensor
Observe the following to ensure the dynami c radar cruise control can function effec- tively.
Otherwise, the radar sensor may not detect correctly and could result in an accident.
●Keep the sensor and grille cover clean at all times. Clean the sensor and grille cover with a soft cloth so you do not mark or damage
them.
●Do not subject the sensor or surrounding area to a strong impact. If the sensor moves even slightly off po sition, the system may become inaccurate or
malfunction. If the sensor or surrounding area is subject to a strong impact, always have the area inspected and adjusted by an y authorized Lexus dealer or repairer, or another duly qualified an d equipped professional.
●Do not disassemble the sensor.
●Do not attach accessories or stickers to the sensor, grille cover or surrounding area.
●Do not modify or paint the sensor and grille cover.
●If the radar sensor needs to be replaced, contact any authorized Lexus dealer or repairer, or another duly qualified and equipped professional.
Page 273 of 640
2734-5. Using the driving support systems
4
Driving
RC300h_EE(OM24740E)
While driving on a road that has lane markers, this system recognizes the lane
markers using a camera as a sensor to alert the driver when the vehicle deviates
from its lane.
If the system judges that the vehicle has de viated from its lane, it alerts the driver
using a buzzer and indications on the multi-information display.
Camera sensor
LDA (Lane Departure Alert)
: If equipped
Summary of function
Page 276 of 640

2764-5. Using the driving support systems
RC300h_EE(OM24740E)
■Temporary cancelation of the LDA system functions
If any of the following occurs, the LDA system functions will be temporarily canceled. The functions will resume after the necessary operating conditions have returned.
●The turn signal lever is operated.
●The vehicle speed deviates from the operating range of the LDA system functions.
●When the lane lines cannot be recognized while driving.
●When the lane departure warning sounds.
The lane departure warning function will not operate again for a several seconds after it has been activated, even if the vehicle leaves the lane again.
■The lane departure warning
Depending on the audio system sound level or air conditioning fan noise while the audio system or air conditioning system is in use, it may be difficult to hear the warning sound.
■After the vehicle has been parked in the sun
The LDA system may not be available and a warning message ( P. 548) will be dis- played for a while after driving has started. When the temperature in the cabin decreasesand the temperature around the camera sensor ( P. 273) becomes suitable for its
operation, the functions will begin to operate.
■If there are lane markers on only one side of the vehicle
The lane departure warning will not operate fo r the side on which lane markers could not
be recognized.
■Conditions in which the function may not operate correctly
In the following situations, the camera sensor may be unable to recognize lane markers
causing the lane departure warning function to operate incorrectly. However, this does not indicate a malfunction.
●When driving through an area with no lane markers, such as a tollbooth, a crossing or
before a ticket checkpoint
●When driving on a sharp curve
●When lane markers are extremely narrow or extremely wide
●When the vehicle leans to one side an unusual amount due to a heavy load or improper tire inflation pressure
●When the following distance between your vehicle and the vehicle ahead is extremely
short
●When the lane markers are yellow (These ma y be more difficult for the system to rec- ognize compared to white markers.)
●When the lane markers are broken, Botts’ dots (raised pavement markers) or stones
●When the lane markers are on a curb etc.
●When lane markers are obscured or partially obscured by sand, dirt, etc.
●When there are shadows on the road running parallel with lane markers, or if a shadow covers the lane markers
●When driving on a partic ularly bright road surface, such as concrete
●When driving on a road surface that is bright due to reflected light
●When driving in a location where the light level changes rapidly, such as the entrance to
or exit from a tunnel